1. Field of the Invention
Embodiments of the present invention generally relate to methods of forming films on substrates, such as semiconductor substrates. More particularly, embodiments of the present invention relate to methods for forming boron rich films on substrates.
2. Description of the Related Art
Integrated circuit geometries have dramatically decreased in size since such devices were first introduced several decades ago. Since then, integrated circuits have generally followed the two year/half size rule (often called Moore's Law), which means that the number of devices on a chip doubles every two years. Today's fabrication facilities are routinely producing devices having 0.13 μm and even 0.1 μm feature sizes, and tomorrow's facilities soon will be producing devices having even smaller feature sizes.
Amorphous boron films have been used in semiconductor processing for various purposes. Amorphous boron has good mechanical properties, excellent step coverage, good wet etch resistance and a high dry etch selectivity for low dielectric films. All of these characteristics are beneficial for applications such as lithographic hard masks to low-k dielectric etching and self-aligned double-patterning processes. However, a problem with amorphous boron is that it tends to have a high film stress which causes line bending and damage the integrated circuit.